Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

Evaluation of the Induced Excitation of the Peripheral Vestibular System Using Micro Scale Inductors

S. Mukesh [1], P. Bhatti [1],
[1] School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA

According to the National Health and Nutrition Examination Survey data, 35 % of US adults aged 40 years and older have evidence of balance dysfunction based on the modified Romberg test. In this vestibular dysfunction, patients are not able to see stabilized images on their retina during head movement. This leads to severe dizziness and vertigo. The severe form of this disability, bilateral ...

Optimal PDE Control Using COMSOL Multiphysics

I. Neitzel[1], U. Prüfert[2], and T. Slawig[3]

[1]Technische Universität Berlin / SPP 1253
[2]Technische Universität Berlin / Matheon
[3]Excellence Cluster The Future Ocean, Algorithmic Optimal Control - Oceanic CO2-Uptake/SPP 1253

An optimal control problem (OCP) is studied to a PDE of elliptic type as well as state constraints. The resulting optimality system contains two PDEs, one algebraic equation and the so called complementary slackness conditions, i.e. dual products between function spaces. At this point, different regularization techniques come into use. In this paper we introduce a Barrier method as one possible ...

Particle Tracing: Analysis of Airborne Infection Risks in Operating Theatres

P. Apell[1], S. Hjalmarsson[1], T. Lindberg[1], I. Wernström[1], Y. Tarakonov[1], A. Erichsen Andersson[2], M. Karlsteen[1]
[1]Department of Applied Physics, Chalmers University of Technology, Göteborg, Sweden
[2]Sahlgrenska University Hospital, Department of Anesthesia, Surgery and Intensive Care, Göteborg, Sweden

Patients undergoing surgery are sensitive to infections. The operation staff may spread 10^4 particles per person per minute, of which ten percent are presumed bacteria-carrying. We visualize the influence of the personnel on the air and particle flows for the two most common ventilation systems in Swedish hospitals using Comsol Multiphysics with particle tracing.. The Laminar Air flow ...

Modeling Acoustic Waveguides for Ear Impedance Measurements

R. Sisto[1], L. Cerini[1], D. Mambro[2], A. Moleti[2], F. Sanjust[1]
[1]INAIL Research, Monteporzio Catone, Italy
[2]Università di Roma, Tor Vergata, Italy

The otoacoustic emissions (OAEs) are acoustic signals emitted by the inner ear as a consequence of the activity of a nonlinear feedback mechanism capable of amplifying the signal near to the hearing threshold level. The otoacoustic emissions can be used as an acoustic imaging of the cochlear functionality. They are used in clinics for screening purposes but due to the extreme variability ...

Photon Migration Through Multiple Layers of Biological Tissue

M.S. Yeoman[1], E. Sultan[2]
[1]Continuum Blue, Tredomen, Ystrad Mynach, United Kingdom
[2]College of Technological Studies, PAAET, Adailiyah, Kuwait

The modeling of light propagation through multiple layers of biological tissue are assessed & compared to the theoretical predictions by Perelman at al. [94 & 95] of the most-favorable-path (MFP). The MFP on which photons will be found can be obtained from the path of the net flux propagation using the diffusion equation. The diffusion equation is valid when studying diffuse light propagation, ...

Elucidating the Mechanism Governing the Cell Rotation Behavior Under DEP

G. Zhang[1], Y. Zhao[1], J. Brcka[2], J. Faguet[2], E. Lee[2]
[1]Clemson University, Clemson, SC, USA
[2]TEL U.S. Holdings, Inc., U.S. Technology Development Center, Austin, TX, USA

In our experiments with manipulating cells with DEP, we noted that some cells are constantly spining. By hypothesing that the cell spining is caused by the non-circular shape of the cell body and the off-centered location of its nucleus and that the rotation direction depends on the relative location of nucleus with respect to the electrical field, we found that the observed cell rotation was ...

Full-Wave Simulation of an Optofluidic Transmission-Mode Biosensor

E. P. Furlani[1], N. M. Litchinitse[2], and R. Biswas[2]

[1]The Institute for Lasers, Photonics and Biophotonics, University at Buffalo, Buffalo, New York, USA
[2]Department of Electrical Engineering, The State University of New York at Buffalo,Buffalo, New York, USA

We present a study of an optofluidic biosensor. The sensor operates in a transmission mode wherein detection is based on a shift in the transmission spectrum caused by the contrast in refractive index between the carrier fluid and the target biomaterial. We study the behavior of the sensor using 2D full-wave electromagnetic analysis, and perform parametric studies of sensitivity as a function ...

Modeling Bacterial Transport and Removal in a Constructed Wetland System

E. Engström, B. Balfors, and R. Thunvik
Royal Institute of Technology, Stockholm, Sweden

In this study we evaluate transport, retention and subsistence of Escherichia coli (E. coli), a common fecal indicator bacteria, in a model (2x1m) of a constructed wetland. Transport occurs in the unsaturated and saturated zone. Inactivation is accounted for as a kinetic first-order process. Retention is assumed to be dominated by solid-air-water interface straining and is modeled with a kinetic ...

Analyzing Drug Delivery and Osteoblast Growth on a Porous Scaffold in a Perfusion Bioreactor

A. Sun, and S. Murray
Dept. of Biomedical Engineering
UCLA, Los Angeles, CA

Implantable Collagen sponges are used in Spinal Surgery as Drug Delivery Scaffolds. An optimal concentration of growth factor that strikes a balance between bone growth and adverse diffusion effects is difficult to find. The porous sponge also serves as a scaffold for Osteoblast growth, and fluid shear has been shown to mediate biological effects on that cell type. We use COMSOL Multiphysics ...

Polymer Compositional Profile Controls By-Product Fate from Erodible Endovascular Scaffolds

T. Shazly, and J. Ferdous
Biomedical Eng., Mechanical Eng. Dept.
University of South Carolina
Columbia, SC

Erodible polymeric scaffolds can mitigate long-term risks associated with permanent implants currently used to treat ischemic artery disease. However, safe deployment of erodible scaffolds is predicated on understanding the interactions between evolved material by-products and local biological tissues. We developed an integrated computational model of polymeric scaffold degradation, by ...